113
FXUS66 KHNX 281019
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
319 AM PDT Fri Jun 28 2024


&&

.KEY MESSAGES...

1. Gusty winds will continue early this morning along the Mojave
Desert Slopes. A Wind Advisory remains in effect from through 8
AM PDT.

2. A warming trend will begin today across central California
with temperature this afternoon 2 to 4 degrees above season
normals.

3. Maximum temperatures are expected to rise above 100 degrees
again over the lower elevations by Saturday and above 105
degrees by next Tuesday.

4. Temperatures will approach 110 degrees in the valley and
desert areas Wednesday, with triple digit heat continuing into
next weekend. An Excessive Heat Watch is in effect from Tuesday
through Saturday.

&&

.DISCUSSION...

Zonal flow aloft currently propagating over central California
will give way to southwesterly winds entering the weekend as an
upper level low pressure system makes its way through the
Pacific Northwest region. Temperatures are projected to
gradually increase with the change in the synoptic pattern.
Ensemble guidance from the National Blend of Models expresses a
10 to 40 percent probability for afternoon temperatures to
exceed 100 degrees in the San Joaquin Valley this afternoon;
however, these probabilities jump to 40 to 70 percent for
Saturday and Sunday. Similar probabilities exist for
temperatures to exceed 105 degrees in the Kern County Desert
through the weekend.

A Wind Advisory continues in the Mojave Desert Slopes through 8
AM PDT this morning due to sustained northwest winds 15 to 25
miles per hour with gusts up to 45 miles per hour. Stronger
winds are also expected in the San Joaquin Valley this evening,
with the HREF ensemble suggesting a moderate to high (50 to 80
percent) probability for wind gusts greater than 20 miles per
hour. This, coupled with minimum relative humidity values
between 10 and 15 percent during the afternoon has led to an
increase in fire danger across the valley areas, especially
where large areas of dry grasses are prevalent.

The end of the weekend will bring the start of a change in the
upper level synoptic flow for the western United States. A
strong upper level ridge is projected to build over California
from the eastern Pacific, remaining relatively stationary over
the region through the week. The stagnant and subsiding air
aloft will create a sharp uptick in probabilities for triple
digit heat across our forecast area. NBM ensemble guidance shows
a 70 to 90 percent probability for 100 degrees in the San
Joaquin Valley each day next week between Tuesday and Sunday.
Early indications show Wednesday, July 3rd to be the warmest
day, with ensembles giving a 75% chance for afternoon
temperatures at least 105 degrees and a 25% chance to exceed 109
degrees. An Excessive Heat Watch has been issued due to the
continuous triple digit heat, valid from 11 AM PDT Tuesday
through 5 AM PDT Saturday. The aforementioned ridge will also
bring clear conditions to the region during the week, offering
little reprieve from the heat.

&&


.AVIATION...
Areas of MVFR and local IFR visibility due to smoke in the
Sierra Nevada and adjacent foothills south of King Canyon. Wind
gusts above 35 knots are possible in the Mojave Desert Slopes
through 15Z this morning, producing local blowing dust.
Otherwise, VFR conditions will prevail across the central
California interior for the next 24 hours.

&&

.AIR QUALITY ISSUES...
Air Quality Alert due to smoke impacts from wildfires.



&&

.CERTAINTY...

The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.html for additional information
and/or to provide feedback.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 8 AM PDT this morning for CAZ338.
Excessive Heat Watch from Tuesday morning through late Friday
night for CAZ300>322-324-332-334-336-338.
&&

$$

public/aviation...SM
IDSS.............DAS

weather.gov/hanford